clean code: remove Deref<Target=RegionKind> impl for Region and use `.kind()`

Signed-off-by: xizheyin <xizheyin@smail.nju.edu.cn>

8 files changed, 26 insertions, 37 deletions

diff --git a/compiler/rustc_middle/src/ty/erase_regions.rs b/compiler/rustc_middle/src/ty/erase_regions.rs
index 8bddb5c0fd7..45a0b1288db 100644
--- a/compiler/rustc_middle/src/ty/erase_regions.rs
+++ b/compiler/rustc_middle/src/ty/erase_regions.rs
@@ -65,7 +65,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for RegionEraserVisitor<'tcx> {
         // We must not erase bound regions. `for<'a> fn(&'a ())` and
         // `fn(&'free ())` are different types: they may implement different
         // traits and have a different `TypeId`.
-        match *r {
+        match r.kind() {
             ty::ReBound(..) => r,
             _ => self.tcx.lifetimes.re_erased,
         }
diff --git a/compiler/rustc_middle/src/ty/flags.rs b/compiler/rustc_middle/src/ty/flags.rs
index b0c442d28f0..2424923fb78 100644
--- a/compiler/rustc_middle/src/ty/flags.rs
+++ b/compiler/rustc_middle/src/ty/flags.rs
@@ -288,7 +288,7 @@ impl FlagComputation {
 
     fn add_region(&mut self, r: ty::Region<'_>) {
         self.add_flags(r.type_flags());
-        if let ty::ReBound(debruijn, _) = *r {
+        if let ty::ReBound(debruijn, _) = r.kind() {
             self.add_bound_var(debruijn);
         }
     }
diff --git a/compiler/rustc_middle/src/ty/fold.rs b/compiler/rustc_middle/src/ty/fold.rs
index dc2c9e3d9f1..8dc73e4ce85 100644
--- a/compiler/rustc_middle/src/ty/fold.rs
+++ b/compiler/rustc_middle/src/ty/fold.rs
@@ -145,10 +145,10 @@ where
     }
 
     fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> {
-        match *r {
+        match r.kind() {
             ty::ReBound(debruijn, br) if debruijn == self.current_index => {
                 let region = self.delegate.replace_region(br);
-                if let ty::ReBound(debruijn1, br) = *region {
+                if let ty::ReBound(debruijn1, br) = region.kind() {
                     // If the callback returns a bound region,
                     // that region should always use the INNERMOST
                     // debruijn index. Then we adjust it to the
diff --git a/compiler/rustc_middle/src/ty/opaque_types.rs b/compiler/rustc_middle/src/ty/opaque_types.rs
index c72efde0994..9445a18ad76 100644
--- a/compiler/rustc_middle/src/ty/opaque_types.rs
+++ b/compiler/rustc_middle/src/ty/opaque_types.rs
@@ -95,7 +95,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for ReverseMapper<'tcx> {
 
     #[instrument(skip(self), level = "debug")]
     fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> {
-        match *r {
+        match r.kind() {
             // Ignore bound regions and `'static` regions that appear in the
             // type, we only need to remap regions that reference lifetimes
             // from the function declaration.
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index 3281cb4135a..0765d066fe9 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -2520,7 +2520,7 @@ impl<'tcx> PrettyPrinter<'tcx> for FmtPrinter<'_, 'tcx> {
 
         let identify_regions = self.tcx.sess.opts.unstable_opts.identify_regions;
 
-        match *region {
+        match region.kind() {
             ty::ReEarlyParam(ref data) => data.has_name(),
 
             ty::ReLateParam(ty::LateParamRegion { kind, .. }) => kind.is_named(),
@@ -2590,7 +2590,7 @@ impl<'tcx> FmtPrinter<'_, 'tcx> {
         // the user might want to diagnose an error, but there is basically no way
         // to fit that into a short string. Hence the recommendation to use
         // `explain_region()` or `note_and_explain_region()`.
-        match *region {
+        match region.kind() {
             ty::ReEarlyParam(data) => {
                 p!(write("{}", data.name));
                 return Ok(());
@@ -2680,7 +2680,7 @@ impl<'a, 'tcx> ty::TypeFolder<TyCtxt<'tcx>> for RegionFolder<'a, 'tcx> {
 
     fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> {
         let name = &mut self.name;
-        let region = match *r {
+        let region = match r.kind() {
             ty::ReBound(db, br) if db >= self.current_index => {
                 *self.region_map.entry(br).or_insert_with(|| name(Some(db), self.current_index, br))
             }
@@ -2704,7 +2704,7 @@ impl<'a, 'tcx> ty::TypeFolder<TyCtxt<'tcx>> for RegionFolder<'a, 'tcx> {
             }
             _ => return r,
         };
-        if let ty::ReBound(debruijn1, br) = *region {
+        if let ty::ReBound(debruijn1, br) = region.kind() {
             assert_eq!(debruijn1, ty::INNERMOST);
             ty::Region::new_bound(self.tcx, self.current_index, br)
         } else {
diff --git a/compiler/rustc_middle/src/ty/region.rs b/compiler/rustc_middle/src/ty/region.rs
index c78306f2ca3..3e4f7a79d53 100644
--- a/compiler/rustc_middle/src/ty/region.rs
+++ b/compiler/rustc_middle/src/ty/region.rs
@@ -1,5 +1,3 @@
-use std::ops::Deref;
-
 use rustc_data_structures::intern::Interned;
 use rustc_errors::MultiSpan;
 use rustc_hir::def_id::DefId;
@@ -22,7 +20,7 @@ impl<'tcx> rustc_type_ir::inherent::IntoKind for Region<'tcx> {
     type Kind = RegionKind<'tcx>;
 
     fn kind(self) -> RegionKind<'tcx> {
-        *self
+        *self.0.0
     }
 }
 
@@ -32,7 +30,7 @@ impl<'tcx> rustc_type_ir::Flags for Region<'tcx> {
     }
 
     fn outer_exclusive_binder(&self) -> ty::DebruijnIndex {
-        match **self {
+        match self.kind() {
             ty::ReBound(debruijn, _) => debruijn.shifted_in(1),
             _ => ty::INNERMOST,
         }
@@ -163,7 +161,7 @@ impl<'tcx> Region<'tcx> {
 
     pub fn get_name(self) -> Option<Symbol> {
         if self.has_name() {
-            match *self {
+            match self.kind() {
                 ty::ReEarlyParam(ebr) => Some(ebr.name),
                 ty::ReBound(_, br) => br.kind.get_name(),
                 ty::ReLateParam(fr) => fr.kind.get_name(),
@@ -185,7 +183,7 @@ impl<'tcx> Region<'tcx> {
 
     /// Is this region named by the user?
     pub fn has_name(self) -> bool {
-        match *self {
+        match self.kind() {
             ty::ReEarlyParam(ebr) => ebr.has_name(),
             ty::ReBound(_, br) => br.kind.is_named(),
             ty::ReLateParam(fr) => fr.kind.is_named(),
@@ -199,32 +197,32 @@ impl<'tcx> Region<'tcx> {
 
     #[inline]
     pub fn is_error(self) -> bool {
-        matches!(*self, ty::ReError(_))
+        matches!(self.kind(), ty::ReError(_))
     }
 
     #[inline]
     pub fn is_static(self) -> bool {
-        matches!(*self, ty::ReStatic)
+        matches!(self.kind(), ty::ReStatic)
     }
 
     #[inline]
     pub fn is_erased(self) -> bool {
-        matches!(*self, ty::ReErased)
+        matches!(self.kind(), ty::ReErased)
     }
 
     #[inline]
     pub fn is_bound(self) -> bool {
-        matches!(*self, ty::ReBound(..))
+        matches!(self.kind(), ty::ReBound(..))
     }
 
     #[inline]
     pub fn is_placeholder(self) -> bool {
-        matches!(*self, ty::RePlaceholder(..))
+        matches!(self.kind(), ty::RePlaceholder(..))
     }
 
     #[inline]
     pub fn bound_at_or_above_binder(self, index: ty::DebruijnIndex) -> bool {
-        match *self {
+        match self.kind() {
             ty::ReBound(debruijn, _) => debruijn >= index,
             _ => false,
         }
@@ -233,7 +231,7 @@ impl<'tcx> Region<'tcx> {
     pub fn type_flags(self) -> TypeFlags {
         let mut flags = TypeFlags::empty();
 
-        match *self {
+        match self.kind() {
             ty::ReVar(..) => {
                 flags = flags | TypeFlags::HAS_FREE_REGIONS;
                 flags = flags | TypeFlags::HAS_FREE_LOCAL_REGIONS;
@@ -275,14 +273,14 @@ impl<'tcx> Region<'tcx> {
 
     /// True for free regions other than `'static`.
     pub fn is_param(self) -> bool {
-        matches!(*self, ty::ReEarlyParam(_) | ty::ReLateParam(_))
+        matches!(self.kind(), ty::ReEarlyParam(_) | ty::ReLateParam(_))
     }
 
     /// True for free region in the current context.
     ///
     /// This is the case for `'static` and param regions.
     pub fn is_free(self) -> bool {
-        match *self {
+        match self.kind() {
             ty::ReStatic | ty::ReEarlyParam(..) | ty::ReLateParam(..) => true,
             ty::ReVar(..)
             | ty::RePlaceholder(..)
@@ -319,15 +317,6 @@ impl<'tcx> Region<'tcx> {
     }
 }
 
-impl<'tcx> Deref for Region<'tcx> {
-    type Target = RegionKind<'tcx>;
-
-    #[inline]
-    fn deref(&self) -> &RegionKind<'tcx> {
-        self.0.0
-    }
-}
-
 #[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
 #[derive(HashStable)]
 pub struct EarlyParamRegion {
diff --git a/compiler/rustc_middle/src/ty/typeck_results.rs b/compiler/rustc_middle/src/ty/typeck_results.rs
index 7c437abfe24..90c6ef67fb8 100644
--- a/compiler/rustc_middle/src/ty/typeck_results.rs
+++ b/compiler/rustc_middle/src/ty/typeck_results.rs
@@ -758,7 +758,7 @@ impl<'tcx> IsIdentity for CanonicalUserType<'tcx> {
                             _ => false,
                         },
 
-                        GenericArgKind::Lifetime(r) => match *r {
+                        GenericArgKind::Lifetime(r) => match r.kind() {
                             ty::ReBound(debruijn, br) => {
                                 // We only allow a `ty::INNERMOST` index in generic parameters.
                                 assert_eq!(debruijn, ty::INNERMOST);
diff --git a/compiler/rustc_middle/src/ty/visit.rs b/compiler/rustc_middle/src/ty/visit.rs
index e3b7a258c39..b341b30af6a 100644
--- a/compiler/rustc_middle/src/ty/visit.rs
+++ b/compiler/rustc_middle/src/ty/visit.rs
@@ -77,7 +77,7 @@ impl<'tcx> TyCtxt<'tcx> {
             }
 
             fn visit_region(&mut self, r: ty::Region<'tcx>) -> Self::Result {
-                match *r {
+                match r.kind() {
                     ty::ReBound(debruijn, _) if debruijn < self.outer_index => {
                         ControlFlow::Continue(())
                     }
@@ -205,7 +205,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for LateBoundRegionsCollector {
     }
 
     fn visit_region(&mut self, r: ty::Region<'tcx>) {
-        if let ty::ReBound(debruijn, br) = *r {
+        if let ty::ReBound(debruijn, br) = r.kind() {
             if debruijn == self.current_index {
                 self.regions.insert(br.kind);
             }
@@ -250,7 +250,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for MaxUniverse {
     }
 
     fn visit_region(&mut self, r: ty::Region<'tcx>) {
-        if let ty::RePlaceholder(placeholder) = *r {
+        if let ty::RePlaceholder(placeholder) = r.kind() {
             self.max_universe = ty::UniverseIndex::from_u32(
                 self.max_universe.as_u32().max(placeholder.universe.as_u32()),
             );